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201.
202.
Characterization of a cytomegalo-like virus isolated from spontaneously degenerated equine kidney cell culture 总被引:8,自引:0,他引:8
203.
I-Shou Chang Sian-Jhih Fu Chung-Hsing Chen Tsung-Hsi Wang Chao A. Hsiung 《Statistics in biosciences》2009,1(1):80-94
Taking households having at least one infective as standard units and considering both a within-household infection rate and
a global infection rate, we propose a Bayesian two level mixing S-I-R (susceptible-infective-removed) counting process model
in which the transmission parameters may change over time and the parameters of interest are the within-household infection
rate and the removal rate. Customized Markov chain Monte Carlo methods are developed for generating samples from the posterior
distribution for inference purpose, based only on the removal times. The numerical performance of this method is examined
in a simulation study. Applying this method to 2003 Taiwan SARS data, we find that the within-household infection rate decreases,
the removal rate increases and their ratio is less than one and decreases significantly during the epidemic. This method allows
the estimation of these parameters during the epidemic. For a rapidly transmitted disease, it provides a method to nearly
real-time tracking of infection measures. 相似文献
204.
205.
CC van Diemen DS Postma M Siedlinski A Blokstra HA Smit HM Boezen 《Respiratory research》2011,12(1):57
Background
An imbalance in Matrix MetalloProteases (MMPs) and Tissue Inhibitors of MMPs (TIMPs) contributes to Chronic Obstructive Pulmonary Disease (COPD) development. Longitudinal studies investigating Single Nucleotide Polymorphisms (SNPs) in MMPs and TIMPs with respect to COPD development and lung function decline in the general population are lacking.Methods
We genotyped SNPs in MMP1 (G-1607GG), MMP2 (-1306 C/T), MMP9 (3 tagging SNPs), MMP12 (A-82G and Asn357Ser) and TIMP1 (Phe124Phe and Ile158Ile) in 1390 Caucasians with multiple FEV1 measurements from a prospective cohort study in the general population. FEV1 decline was analyzed using linear mixed effect models adjusted for confounders. Analyses of the X-chromosomal TIMP1 gene were stratified according to sex. All significant associations were repeated in an independent general population cohort (n = 1152).Results
MMP2 -1306 TT genotype carriers had excess FEV1 decline (-4.0 ml/yr, p = 0.03) compared to wild type carriers. TIMP1 Ile158Ile predicted significant excess FEV1 decline in both males and females. TIMP1 Phe124Phe predicted significant excess FEV1 decline in males only, which was replicated (p = 0.10) in the second cohort. The MMP2 and TIMP1 Ile158Ile associations were not replicated. Although power was limited, we did not find associations with COPD development.Conclusions
We for the first time show that TIMP1 Phe124Phe contributes to excess FEV1 decline in two independent prospective cohorts, albeit not quite reaching conventional statistical significance in the replication cohort. SNPs in MMPs evidently do not contribute to FEV1 decline in the general population. 相似文献206.
Yun‐Sheng Lin Ahmed Eid Fazary Chung‐Hsiung Chen Yao‐Haur Kuo Ya‐Ching Shen 《化学与生物多样性》2011,8(7):1310-1317
Chemical investigation of the Taiwanese soft coral Asterospicularia laurae has led to the isolation of three new xenicane diterpenoids, named asterolaurins K–M ( 1 – 3 , resp.). Their chemical structures were determined through extensive spectroscopic analyses (1H‐ and 13C‐NMR, 1H,1H‐COSY, HMBC, and NOESY). Compound 2 exhibited cytotoxic activity against HEp‐2, Daoy, MCF‐7, and WiDr tumor cells. 相似文献
207.
An C. Hsiung W. Alice Boyle Robert J. Cooper Richard B. Chandler 《Biological reviews of the Cambridge Philosophical Society》2018,93(4):2049-2070
Animal migration has been the subject of intensive research for more than a century, but most research has focused on long‐distance rather than short‐distance migration. Altitudinal migration is a form of short‐distance migration in which individuals perform seasonal elevational movements. Despite its geographic and taxonomic ubiquity, there is relatively little information about the intrinsic and extrinsic factors that influence altitudinal migratory behaviour. Without this information, it is difficult to predict how rapid environmental changes will affect population viability of altitudinal migrants. To synthesize current knowledge, we compiled literature on altitudinal migration for all studied taxa, and identified the leading hypotheses explaining this behaviour. Studies of animal altitudinal migration cover many taxonomic lineages, with birds being the most commonly studied group. Altitudinal migration occurs in all continents except for Antarctica, but about a third of the literature focused on altitudinal migration in North America. Most research suggests that food and weather are the primary extrinsic drivers of altitudinal migration. In addition, substantial individual‐level variation in migratory propensity exists. Individual characteristics that are associated with sex, dominance rank, and body size explain much of the variation in migratory propensity in partially migratory populations, but individual‐level correlates are poorly known for most taxa. More research is needed to quantify the effects of habitat loss, habitat fragmentation, and climate change on altitudinal migrants. Demographic studies of individually marked populations would be particularly valuable for advancing knowledge of the cascading effects of environmental change on migratory propensity, movement patterns, and population viability. We conclude our review with recommendations for study designs and modelling approaches that could be used to narrow existing knowledge gaps, which currently hinder effective conservation of altitudinal migratory species. 相似文献
208.
Salvisertin A,a New Hexacyclic Triterpenoid,and Other Bioactive Terpenes from Salvia deserta Root
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Yin‐Ru Wang Yun Yu Shu‐Ming Li Wei Liu Wei Li Susan L. Morris‐Natschke Masuo Goto Kuo‐Hsiung Lee Xue‐Feng Huang 《化学与生物多样性》2018,15(4)
Using various chromatographic methods, a new hexacyclic triterpenoid, 2β,3β,24β‐trihydroxy‐12,13‐cyclotaraxer‐l4‐en‐28oic acid ( 1 ), together with ten known compounds, 2α,3α,23‐trihydroxyurs‐12,20(30)‐dien‐28oic acid ( 2 ), 6,7‐dehydroroyleanone ( 3 ), horminone ( 4 ), 7‐O‐methylhorminone ( 5 ), sugiol ( 6 ), demethylcryptojaponol ( 7 ), 14‐deoxycoleon U ( 8 ), 5,6‐didehydro‐7‐hydroxy‐taxodone ( 9 ), ferruginol ( 10 ), and dichroanone ( 11 ), were isolated from the roots of Salvia deserta. Their structures were identified on the basis of spectroscopic analysis and comparison with the reported data. The individual compounds ( 1 , 3 – 8 ) were screened for cytotoxic activity, using the sulforhodamine B bioassay (SRB) method. As the results, Compounds 3 , 5 , and 8 showed cytotoxic potency against A549, MDA‐MB‐231, KB, KB‐VIN, and MCF7 cell lines with IC50 values ranging from 6.5 to 10.2 μm . 相似文献
209.
Wu JH Chang FR Hayashi Ki Shiraki H Liaw CC Nakanishi Y Bastow KF Yu D Chen IS Lee KH 《Bioorganic & medicinal chemistry letters》2003,13(13):2223-2225
A new inhibitor of in vitro tumor cell replication, cappamensin A (1) (2H-1,4-benzoxazin-3(4H)-one, 6-methoxy-2-methyl-4-carbaldehyde), was isolated from the roots of Capparis sikkimensis subsp. formosana using bioactivity-guided fractionation. The structure of 1 was established by spectroscopic methods, including 2D NMR analyses. Compound 1 displayed significant in vitro anticancer activity against ovarian (1A9), lung (A549), ileocecal (HCT-8), breast (MCF-7), nasopharyngeal (KB), and vincristine resistant (KB-VIN) human tumor cell lines with ED(50) values =4 microgram/mL (mean GI(50) value of 15.1 microM). 相似文献
210.
Shu-Chen Kan Wei-Feng Chang Min-Chi Lan Chia-Chi Lin Wei-Shiang Lai Chwen-Jen Shieh Kuang-Pin Hsiung Yung-Chuan Liu 《Analytical biochemistry》2015
In this study, a dry assay of l-lactate via the enzymatic chromatographic test (ECT) was developed. An l-lactate dehydrogenase plus a nicotinamide adenine dinucleotide (NADH) regeneration reaction were applied simultaneously. Various tetrazolium salts were screened to reveal visible color intensities capable of determining the lactate concentrations in the sample. The optimal analysis conditions were as follows. The diaphorase (0.5 μl, 2−6 U/μl) was immobilized in the test line of the ECT strip. Nitrotetrazolium blue chloride (5 μl, 12 mM), l-lactate dehydrogenase (1 μl, 0.25 U/μl), and NAD+ (2 μl, 1.5 × 10−5 M) were added into the mobile phase (100 μl) composed of 0.1% (w/w) Tween 20 in 10 mM phosphate buffer (pH 9.0), and the process was left to run for 10 min. This detection had a linear range of 0.039 to 5 mM with a detection limit of 0.047 mM. This quantitative analysis process for l-lactate was easy to operate with good stability and was proper for the point-of-care testing applications. 相似文献